No, x-rays do not travel slower than infrared radiation or even the opposite. Both are travelling in vacuum therefore they travel at same speed. They differ in the frequency of the electromagnetic waves.
The average atomic mass of the imaginary element : 47.255 amu
<h3>Further explanation </h3>
The elements in nature have several types of isotopes
Isotopes are elements that have the same Atomic Number (Proton)
Atomic mass is the average atomic mass of all its isotopes
Mass atom X = mass isotope 1 . % + mass isotope 2.% ..
isotope E-47 47.011 amu, 87.34%
isotope E-48 48.008 amu, 6.895
isotope E-49 50.009 amu, 5.77%
The average atomic mass :

No, because hydrogen isn’t brought out of the equation
Answer:
B
Explanation:
Ethanol is C2H6O. Carbon diozidex is CO2. Ethanol has hydgrogen, where carbon dioxide does not.